MONROE, FORT, the most extensive work of a defensive character in the United States, formerly known as Fortress Monroe. It is situated at the end of the peninsula of Old Point Comfort, Va., between the York and the James rivers. The work was begun in 1817 (the year of the election of President Monroe for whom it was named). At the outbreak of the Civil War, it covered an area of 65 acres; the garrison consisted of 300 men, and the ordinance comprised 400 great guns. It was known that the Confederates had designs upon the fort, and Gen. B. F. Butler, commander of the Department of Viriginia, made it his headquarters and reinforced the garrison. The Nationals continued in possession till the close of the war. Since then an important artillery school has been located there.